Aircraft seat

ABSTRACT

An aircraft seat includes a hollow seat structure that is made from a single layer of a reinforced composite material. In a unitary construction, the seat structure has a seat portion and a backrest, and it is formed with a convex surface that is located under the seat portion. A base frame formed with a concave surface is attached to the aircraft fuselage, and it is oriented for juxtaposition with the convex surface of the seat structure to provide for a relative sliding motion of the seat structure on the base frame. A connector is also provided for selectively holding the convex surface of the seat structure in a fixed orientation relative to the concave surface of the base frame.

FIELD OF THE INVENTION

The present invention pertains generally to seats for aircraft. More particularly, the present invention pertains to aircraft seats that can be rotated on a curved surface and selectively affixed in either an upright or a reclining orientation. The present invention is particularly, but not exclusively, useful as an aircraft seat that is made of a reinforced composite material and has a substantially hollow, light-weight structure.

BACKGROUND OF THE INVENTION

In the design of a seat for an aircraft, at least three aspects of the seat require particularly careful consideration. These aspects are: safety, weight and space requirements. Of these, safety is clearly the most important.

With specific regard to the safety features of an aircraft seat, federal regulations require such a seat be able to withstand impact loads of as much as 19 g's at 600 down, and 26 g's forward with a 10° yaw and floor deformation. Additionally, the seat must resist commensurate forces in the fore and aft, as well as lateral, directions. Stated differently, the seat must be designed to withstand loads that can be survived by the seat's occupant (i.e. a human being) without severe spinal injury. In this context, engineering considerations lead to the conclusion that the adverse effects of an impact force can be significantly ameliorated by distributing the load over a greater area of the seat and, consequently, over a greater portion of its occupant.

Insofar as weight is a concern in the design of an aircraft seat, its significance is clearly set forth in the weight and balance data required for each aircraft. Simply stated, aircraft performance is directly affected by weight. In this case; less is best. On the other hand, for a given material, its ability to withstand load forces (i.e. its strength as a safety factor) is enhanced by using more material (i.e. increased weight). Fortunately, several very strong, light-weight materials are now available (e.g. composite materials). Thus, material strength for safety purposes can be obtained without unnecessarily sacrificing too much in weight.

From a commercial perspective, the space requirements for an aircraft seat pose several important considerations. Specifically, in order to accommodate more passengers on the aircraft, smaller seat space requirements are necessary. At the same time, for personal comfort, persons flying on the aircraft cannot be unreasonably confined. For instance, on long duration flights (e.g. flights greater than about an hour), it is almost imperative that the seat be adjustable to allow for some personal movement. Typically, this is accomplished by having the seat be somehow moveable between a “reclined” position and an “upright” position. Heretofore, this transition has been accomplished by merely changing the inclination of the backrest portion of the seat relative to its seat portion. Such a seat reconfiguration, however, may be limited by the presence of a bulkhead in the aircraft, or by the need to maintain accessibility to specific areas such as emergency exits.

Although many different types of seats have been developed with occupant comfort being the foremost concern, for reasons set forth above, other considerations may be of overriding concern in the case of an aircraft seat. One type of seat configuration is particularly noteworthy. Namely, a seat having a convex underside resting on a concave surface of same radius of curvature is capable of substantially addressing the concerns mentioned above. Such a structure allows the seat to be selectively moved between an “upright” and a “reclined” orientation, without the necessity of reconfiguring the seat. Moreover, this reorientation can be done without intruding beyond a predefined space for the seat. Further, with an ability to prepare for impact by easily assuming a reclined position, a vertical impact load can be more effectively distributed over the seat and its occupant. Also, in a “reclined” orientation, portions of the seat structure itself are repositioned to better resist fore and aft movements of the occupant. Thus, an ability to reorient a seat, while confining it within a predefined space, can be beneficial for at least two reasons. For one, the seat can be oriented for increased safety. For another, the seat will always satisfy prescribed space requirements.

In light of the above, it is an object of the present invention to provide an aircraft seat that will satisfy regulatory requirements for aircraft safety, while limiting the addition of weight to the aircraft. Another object of the present invention is to provide an aircraft seat that can be easily reoriented between “reclined” and “upright” positions for increased passenger safety, without intruding beyond a predefined space envelope. Yet another object of the present invention is to provide for an aircraft seat that is easy to use, is relatively simple to manufacture, and is comparatively cost effective.

SUMMARY OF THE INVENTION

In accordance with the present invention, an aircraft seat is provided that can be easily reoriented for greater safety and comfort of the occupant, while confining the seat to movement within a predetermined space. Structurally, the aircraft seat includes a base frame that is affixed to the fuselage of the aircraft. It also includes a seat structure that rests on the base frame. Importantly, the seat structure can move relative to the base frame and be selectively held by a connector in a variety of fixed orientations on the base frame.

For the present invention, the seat structure of the aircraft seat is of unitary construction. As parts of this unitary construction, the seat structure includes a seat portion with a backrest that is inclined at a predetermined angle to the seat portion (e.g. approximately 105°). Also, as part of this unitary construction, the seat portion includes a convex surface, or a plurality of convex rails, that extends across the underside of the seat portion. Preferably, this convex surface extends from a front edge of the seat portion to a point behind the backrest. Dimensionally, the convex surface of the seat portion will have a radius of curvature “R” measured from a line that lies opposite the seat portion from the convex surface, and is mutually parallel to the plane of the seat portion and to the plane of the backrest. In general, “R” will be around three feet.

The base frame of the aircraft seat is rigidly affixed to the fuselage of the aircraft, and it is formed with a concave surface that corresponds with the convex surface of the seat structure. Thus, when the seat structure is juxtaposed with the base frame (i.e. there is a mating engagement of the convex surface of the seat structure with the concave surface of the base frame), the seat structure is set for rotation about the line from which “R” is measured. With this rotation, the seat structure can be selectively positioned on the base frame in either an “upright” position, or a “reclined” position. Further, the seat portion can be held stationary in any selected position by the connector. As indicated above, the convex surface can comprise a plurality of rails. In that case, the base frame will comprise a corresponding number of concave surfaces.

In the manufacture of the aircraft seat of the present invention, the entire seat structure can be essentially formed as a layer of composite material. Specifically, the seat portion, the backrest, and the convex surface can all be pre-formed and co-cured as a unit to establish the intended unitary construction for the seat structure. Similarly, the entire base frame can be pre-formed and co-cured as a unit. The result is a substantially hollow seat structure and a substantially hollow base frame that, together, are extremely light-weight. The seat structure and the base frame can then be reinforced, if necessary, and provided with cushions, seat belts, and any other accessories that may be desirable.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:

FIG. 1 is an exploded perspective view of an aircraft seat in accordance with the present invention;

FIG. 2 is a front elevation view of a row of aircraft seats of the present invention, with the seats mounted in the fuselage of an aircraft; and

FIG. 3 is a side view of aircraft seats mounted as seen along the line 3-3 in FIG. 2, with a forward aircraft seat in an “upright” position (with portions broken away for clarity), and with an aft aircraft seat in a “reclined” position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring initially to FIG. 1 an aircraft seat in accordance with the present invention is shown and is generally designated 10. As shown, the aircraft seat 10 has two essential parts: a seat structure 12 and a base frame 14. Formed together, in a unitary construction, the seat structure 12 includes a seat portion 16 and a backrest 18, with the backrest 18 being inclined relative to the seat portion 16. For this inclination the angle “α” shown in FIG. 1 is about seventy five degrees (α≈75°). Additionally, it is also shown in FIG. 1 that the seat portion 16 of the seat structure 12 includes a convex surface 20. A headrest 22 (not part of the unitary construction) is mounted on the backrest 18 so it can be adjusted for the comfort of the seat occupant (not shown).

Still referring to FIG. 1, it will be seen that the base frame 14 is formed with a concave surface 24. As shown, the base frame 14 can also have a connector 26 that is used for holding the seat structure 12 in a selected orientation on the base frame 14. As will be appreciated by the skilled artisan, the connector 26 could just as well be placed on the seat structure 12 for the same purpose. In any event, it is important that the convex surface 20 dimensionally correspond with the concave surface 24. Accordingly, the concave surface 24 of the base frame 14 will have a substantially same radius of curvature “R” as does the convex surface 20 of the seat structure 12. In detail, it will be appreciated that each seat portion 16 has a forward edge 28, and that the convex surface 20 extends from this forward edge 28 to a line of points 30 that is located behind the backrest 18. Geometrically, the convex surface 20 is determined by the magnitude of the radius of curvature “R”. Further, “R” is measured from the line 32 and is about three feet in length (R≈3 ft). As shown, the line 32 from which “R” is measured is located between a plane that is defined by the seat portion 16 and a plane that is defined by the backrest 18. Also, the plane that is defined by the seat portion 16 lies between the line 32 and the convex surface 20.

FIG. 2 shows that the aircraft seat 10, as intended for the present invention, is fixedly mounted in the cabin of an aircraft fuselage 34. FIG. 2 also shows the aircraft seat 10 positioned along with another companion seat 10′ of the same construction. As further shown in FIG. 3, it is intended that in addition to the side-by-side locations of seats 10 and 10′ (FIG. 2), they will also be positioned fore and aft of each other. Further, a seat 10 can be installed to face forward in the aircraft or, alternatively, to face aft. With this in mind, the ability of the aircraft seat 10 to safely and comfortably accommodate a person is important.

Referring now to FIG. 3, the operation and the unitary construction of an aircraft seat 10 is best appreciated by comparing the representative aircraft seats 10 a and 10 b to each other and to aircraft seat 10 shown in FIG. 1. Specifically, with cross reference to FIG. 1, FIG. 3 shows that when the seat structure 12 is mounted onto the base frame 14, an interface 36 is established between the convex surface 20 of the seat structure 12 and the concave surface 24 of the base frame 14. Due to the capability for relative motion between the seat structure 12 and the base frame 14 at the interface 36, the seat structure 12 is able to move back and forth along the path 38. This allows the seat structure 12 to be reoriented between an “upright” orientation (aircraft seat 10 a) and a “reclined” orientation (aircraft seat 10 b). Importantly, any reorientation of an aircraft seat 10 does not require a reconfiguration of the seat 10. Instead, it involves only movements along the path 38 and will, thus, effectively confine the aircraft seat 10 to a predefined space.

Referring still to FIG. 3, it is shown that the aircraft seat 10 a is essentially a single layer 40 made of multiple plies of a material. Thus, as envisioned for the present invention, the seat portion 16, backrest 18 and convex surface 20 of the seat structure 12 are pre-formed and co-cured, as a unit. Preferably, the layer 40 is made of a composite material, such as carbon fiber/epoxy (i.e. graphite), or some other material such as fiber glass, KEVLAR® or SPECTRA®. Similarly, as also indicated for aircraft seat 10 a in FIG. 3, the base frame 14 can have a similar construction. The consequence of this construction is that both the seat structure 12 and the base frame 14 are substantially hollow. Further, as shown for the seat structure 12 of aircraft seat 10 a, reinforcements 42 can be employed in combination with the layer 40 to improve the stiffness of the layer 40. Preferably, the reinforcements 42 that are used for this purpose are of a type generally disclosed in U.S. Patent Application Publication No. US2004/0070108 A1, which is assigned to the same assignee as the present invention.

It will be appreciated by the skilled artisan that the seat 10 can include additional accessories (not shown). For example, seat belts with or without shoulder harnesses can be provided for passengers and crew. Also, these seat restraints can be installed to include emergency-inflatable air bags. It will be further appreciated that the comfort and safety of the occupant of a seat 10 can be enhanced by using foam pads on the seat 10. In addition to the above-mentioned accessories, and in order to strengthen the seat 10, the present invention envisions the seat 10 may include a core (not shown) of light weight material, such as balsa wood, or an internal core structure, such as honeycomb.

For an alternate embodiment of the aircraft seat 10 of the present invention, FIG. 1 shows that the convex surface 20 may include a plurality of rails 44, of which the rails 44 a and 44 b are exemplary. If used, these rails 44 a and 44 b will each present a respective convex surface for the same purposes as disclosed above for the single convex surface 20. In this alternate embodiment, the base frame 14 will be formed with depressions (grooves) 46 a and 46 b that respectively correspond to the rails 44 a and 44 b. Accordingly, the depressions (grooves) 46 a and 46 b will each present a concave surface 24 for the same purposes as disclosed above for the single concave surface 24. As will be appreciated by the skilled artisan, the locations of the depressions (grooves) and rails can be reversed.

While the particular Aircraft Seat as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims. 

1. An aircraft seat for attachment to an aircraft fuselage which comprises: a layer of composite material formed as a seat structure having a seat portion and a backrest, said layer of composite material also being formed with a convex surface, wherein the seat portion defines a plane and the backrest defines a plane and wherein the convex surface of the seat structure has a radius of curvature “R” measured from a line, and further wherein the seat portion is between the line and the convex surface, with the line being substantially parallel to the plane of the seat portion and to the plane of the backrest; a base frame attached to the aircraft fuselage, wherein said base frame is formed with a concave surface for juxtaposition with the convex surface of the seat structure to provide for a relative sliding motion therebetween; and a connector for selectively holding the convex surface of the seat structure in a fixed orientation relative to the concave surface of the base frame.
 2. An aircraft seat as recited in claim 1 wherein the convex surface of the seat structure and the concave surface of the base frame have a same radius of curvature “R”.
 3. An aircraft seat as recited in claim 1 wherein the seat structure is substantially hollow.
 4. An aircraft seat as recited in claim 1 further comprising a headrest positioned on the backrest for adjustment to support a person sitting in said seat.
 5. An aircraft seat as recited in claim 1 wherein the concave surface of said base frame comprises a plurality of mutually parallel rails, and the seat portion of said seat structure comprises a respective plurality of convex surfaces.
 6. An aircraft seat as recited in claim 1 wherein the composite material is carbon fiber/epoxy and said seat further comprises a seat belt for holding a person on said aircraft seat.
 7. An aircraft seat as recited in claim 1 further comprising a reinforcing member selectively affixed to said layer to provide rigidity for said seat.
 8. An aircraft seat for attachment to an aircraft fuselage which comprises: a hollow seat structure having a seat portion integral with a convex surface and a backrest integral with the seat portion, wherein the seat portion defines a plane and has a substantially straight forward edge with the convex surface extending from the forward edge of the seat portion to a line behind the backrest, with the seat portion substantially between the convex surface and the backrest, and with the convex surface distanced from the seat portion to establish a hollow space therebetween; a base frame attached to the aircraft fuselage, wherein said base frame is formed with a concave surface for juxtaposition with the convex surface of the seat structure to provide for a relative sliding motion therebetween; and a connector for selectively holding the convex surface of the seat structure in a fixed orientation relative to the concave surface of the base frame.
 9. An aircraft seat as recited in claim 8 wherein said seat structure is made with a layer of composite material of carbon fiber/epoxy.
 10. An aircraft seat as recited in claim 8 wherein the backrest defines a plane and wherein the convex surface of the seat structure has a radius of curvature measured from a line located opposite the seat portion from the convex surface, with the line being substantially parallel to the plane of the seat portion and to the plane of the backrest.
 11. An aircraft seat as recited in claim 10 wherein the convex surface of the seat structure and the concave surface of the base frame have a same radius of curvature “R”.
 12. An aircraft seat as recited in claim 8 further comprising a reinforcing member selectively affixed to said seat structure to provide rigidity for said seat.
 13. An aircraft seat as recited in claim 8 wherein the concave surface of said base frame comprises a plurality of mutually parallel rails, and the seat portion of said seat structure comprises a respective plurality of convex surfaces.
 14. An aircraft seat as recited in claim 8 further comprising: a seat belt for holding a person on said aircraft seat; and a headrest positioned on the backrest for adjustment to support a person sitting in said seat.
 15. An aircraft seat for attachment to an aircraft fuselage which comprises: a base frame affixed to the aircraft, wherein the base frame is formed with at least one concave surface and wherein the concave surface is characterized by having a radius of curvature “R”; a seat structure formed with a convex surface having a same radius of curvature “R”, with the convex surface of the seat structure juxtaposed with the concave surface of the base frame to provide for a relative sliding motion therebetween; and a connector for selectively holding the seat structure in a fixed orientation relative to the base frame.
 16. An aircraft seat as recited in claim 15 wherein the concave surface of the base frame is a depression, and the convex surface of the seat structure is a rail.
 17. An aircraft seat as recited in claim 15 wherein the radius of curvature “R” is approximately three feet.
 18. An aircraft seat as recited in claim 15 comprising a plurality of mutually parallel concave surfaces on the base frame, and a respective plurality of mutually parallel convex surfaces on the seat structure.
 19. An aircraft seat as recited in claim 15 wherein the seat structure is of unitary construction and is formed with a seat portion and a backrest configured in combination to support a person, and wherein the seat structure further comprises a reinforcing member selectively affixed thereto to provide rigidity for the seat.
 20. An aircraft seat as recited in claim 15 wherein the seat structure is made with a layer of composite material of carbon fiber/epoxy. 